The present invention generally relates to the field of navigational systems and more particularly to a method for increasing the accuracy of range measurements between data link systems.
Reducing measurement noise in range measurements is essential to maintaining navigational accuracy of a system that is dependent on ranging to produce or enhance its navigational solution. With current data link systems, ranging accuracy between platforms is highly dependent on the clock bias between the interrogator and the responder, with every nanosecond of clock bias between the systems resulting in approximately one foot of additional ranging error.
Current systems such as the joint tactical information distribution system (JTIDS) attempt to reduce this ranging error by actively synchronizing the clocks between systems. However there is a practical limit to how accurately the systems can be time synched. Any unresolved clock bias in these systems will result in ranging error.